But at the same time teachings should be reasonable, they should facilitate human happiness and quality of life.
Isn’t the promotion of human happiness the reason why things like helping the poor, fighting against oppression, working to cure diseases etc. are all considered good and noble?
I don’t think it makes sense to ask a husband and wife to abstain from sexual relations. Sexual intimacy is a way for a couple to express love, to be close, to strengthen their marriage.
Abstinence may be a good idea if the husband has AIDS, but if he has something that can be cured, or that isn’t as serious, or something that condoms are effective against, then why not use condoms? Doing so will allow the spouses to express their love for each other physically and will protect both the woman and the unborn child from an STD.
Where is the evil in that? And don’t tell me “the Church says it’s evil”, that’s not enough for me, explain why it’s evil and perhaps I will agree with you.